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RA: 23h 30m 7s
Dec: +49° 08′ 0″
Ch: MSA:1100, U2:88, SA:9
Ref: SIMBAD, Collinder (1931), DAML02, Archinal&Hynes (2003)
Type: open cluster, 32p
Mag: B=6.79, V=5.6
Synonyms: H VIII-069
Discovered in 1787 by William Herschel with an 18.7-inch f/13 speculum telescope. He called it "a cluster of coarsely scattered pretty large stars, one 8th mag in the S.f. part."
(Lick Obs Bul, Vol 14, No. 420) gives the diameter as 13' and the class as 1 3 p.
(Sulentic and Tifft 1973) notes that this is a 8.0 mag open cluster.
Becker, W. (1963) Die raumliche Verteilung von 156 galaktischen Sternhaufen in Abhangigkeit von ihrem Alter. Z. Astrophys., 57, 117. [comment on non-existent clusters]
"Bemerkungen: Die Objekte NGC 1807, NGC 7686, Tr.84 fehlen im Katalog, da sie keine realen Sternhaufen sind."
Houston writes: "A star just at the limit of naked-eye visibility is involved with NGC 7686. My 10-inch showed about 50 stars in a 15'-diameter circle. This cluster has a very irregular shape, and strings of stars form a prominent Y pattern with a large arrowhead nearby."
described as "loose and poor with some 35 stars counted. Has a bright red-orange stars situated within the cluster. 8-inch, 48x."
writes in "The Focal Point", Volume 6, No. 2 (1993) "NGC 7686 A small, sparse open cluster surrounding a wide orange and blue double star. Not well detached from the background, I counted only about 15 relatively faint stars in the cluster."
Lorenzin, in the e-version of "1000+ The Amateur Astronomers' Field Guide to Deep Sky Observing", notes: "7M; 12' diameter; 12-plus 7M thru 13M members; large irregular and sparse; knot of dimmer stars surrounds brightest member E of center of knot."
6cm - around a br *, mostly N&E sides. only ten *s, irreg scattered.
25cm - 25' diam w/45 *s. m6.5 central * is greenish. *s loosely concen; an empty space on S. not interesting. BS.
30cm - not a bad cl, 50 *s in 15' diam. loose and unconcen. br * nr center is red. stragglers to 25'. pairs on Lick plates not obvious: too widely sep. CBL, Roof.
Alldays (22.50S, 20.12E, 770m).
12-inch f/10 SCT (95x)
Bright scattered cluster with stars in strings and a lovely 6 magnitude orange star in the middle. Slightly more compact middle.
The Messier objects
The Bennett objects
The Caldwell list
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